Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
The Client ID is valid but not allowed by this Server.
Defined in header <boost/mqtt5/reason_codes.hpp>
constexpr
boost::mqtt5::reason_code client_identifier_not_valid { 0x85 };
Convenience header <boost/mqtt5.hpp>